The present invention relates to the use of seedmeal from meadowfoam, genus Limnanthes, or like plants to exogenously achieve plant growth enhancement. The present invention also relates to application rates, with and without fertilizer, to achieve this enhanced growth.
Plant growth enhancement is a major industry and a paramount concern of agricultural food producers, ornamental stock producers and many residential and commercial landowners. Fertilizer manufacture and distribution is a principal component of the plant growth industry. While fertilizer may take many forms including waste material and manure, commercial fertilizer often consists of nitrogen, phosphorous and potassium (typically abbreviated NPK). In addition to other cellular destinations, nitrogen and phosphorous are needed to construct a cell""s DNA, a copy of which is required for each cell division. Nitrogen and phosphorous are typically absorbed through the roots in elemental form or in combination with other atoms, e.g., as small subsets of larger compounds. The availability and uptake of NPK and to a lesser extent other molecules may substantially affect plant growth and yield.
Plant growth is also affected by the presence of plant growth substances, often referred to as xe2x80x9chormones,xe2x80x9d that are produced in plant tissue and at low concentrations promote, inhibit or qualitatively affect plant growth. Note that these substances are not energy sources or nutrients. Plant growth hormones may generally be grouped into five recognized categories. These are: ethylene and like molecules that promote ripening; abscisic acids that are involved in dormancy and abscission; auxins that stimulate cell extension (typically in actively growing regions); gibberellins that are involved in shoot extension in light; and cytokinins that are often found in roots and involved in cell division and interact with auxin to determine whether dividing cells become root or shoot cells.
The effect of exogenous plant hormones-on recipient plant growth and on fertilizer uptake is not well known, and there is very; limited documentation of successful exogenous plant hormone facilitated plant growth (see reference below). Procurement and application of plant hormones may also be difficult. For these reasons, amongst, others, plant growers typically rely on the application of large amounts of fertilizer as the primary, if not exclusive, way of enhancing plant growth, and not application of plant hormone like substances.
Conventional fertilizer application techniques make large amounts of NPK and similar substances available to plants. These techniques are disadvantageous, however, in that significant quantities of the applied fertilizer are not absorbed by the plant but are blown or washed off into neighboring waterways, often resulting in algae blooms and some degree of putrification of those water resources. A need thus exists to provide plant growth enhancement in a way that replaces conventional fertilizing processes or enhances those processes such that less fertilizer is required and/or that which is applied is more likely to be absorbed by the plant.
Other prior art efforts to increase plant growth include agricultural biotechnology techniques. Agricultural biotechnology may manifest itself in many ways including modification of genes related to: nutrient uptake, de novo synthesis of nutrients; cell elongation; disease resistance; and/or flowering; etc. While agricultural biotechnology holds promise, it is viewed with great suspicion by society due to potential malevolent environmental ramifications. Agricultural biotechnology techniques for plant growth enhancement are also disadvantageous in that they are extremely expensive, long in development and uncertain in their useful lives. A need thus exists to provide plant growth enhancement that does not rely primarily on agricultural biotechnology or xe2x80x9cmolecular engineeringxe2x80x9d techniques.
In general, seeds accumulate and store a number of compounds including fatty acids, proteins, sugars, hormones, phenolic acids, tannins and mineral nutrients. Often the hormones or related growth enhancing substances are configured in such a manner or provided in concentrations that render them effective only for the same type of plant. This may to some extent seem intuitive in that in being efficacious to only the same type of plant, they do not facilitate growth of a different type of plant that might compete with their xe2x80x9cchildxe2x80x9d plant. Studies using seedmeal from mustard seed and rape seed plants found limited or no growth enhancement (Oleszek et at., 1994; Johansson and Ascard, 1994, for mustard and Waddington, 1978, for rape seed). Growth stimulus in plant species other than Limnanthes has been attributed to supplemental mineral nutrients present in their seedmeal. There is no evidence from prior studies using seedmeals that shows significant growth enhancement similar to that discussed herein. Experiments using synthetic auxins, cytokinins and/or oligosaccharins have, however, shown that these compound may be involved in limited cell elongation in in vitro grown pea and oat coleoptiles when applied exogenously (Katekar, 1999; Fry, 1999).
To overcome the limitations of prior art plant growth enhancement techniques (often fertilizer based) and to favorably contribute to the critical challenge of increasing plant growth and production, the present invention includes recognition of the exceedingly beneficial effect of meadowfoam seedmeal (MSM) on plant growth and the use of suitable MSM and like substances in this capacity. The present invention includes the use of MSM and like substances in appropriate concentrations, with and without fertilizer, and in various growing media arrangements (e.g., top-dressed, mixed, etc.) to promote plant growth. The beneficial growth attributed to certain concentrations of MSM is apparently achieved, at least in part, by the presence of widely applicable and exceedingly efficacious exogenous hormone like substances (HLS) from MSM. In a top-dressed or mixed media arrangement the growing medium is approximately 7% or less MSM and more desirably from approximately 2-5% MSM. Concentrations above approximately 7.5% by volume tend to have less growth enhancement (in most but not all plants) than concentrations of 2-5% and may even have deleterious effects on plant growth including agravatrophic response.
The present invention includes providing seedmeal that effects plant growth in a manner similar to the beneficial results discussed herein. The plant used in the below discussion is meadowfoam, genus Limnanthes, and particularly the variety Limnanthes alba Hartweg ex. Benth (Benth). Since the beneficial properties of Benth are conferred by its genome, any plant having a similar genetic composition in the relevant locations can exhibit the beneficial growth characteristics discussed herein and is thus within the present invention.
The present invention also includes methods of combining MSM with planting medium materials, with and without fertilizer and/or other substances, to achieve a planting medium that enhances plant growth. This combining may include mixing, top-dressing or other ways of combining the MSM or like substances other planting medium material.